The past two weeks there has been a late model Mustang Shelby at my kids' school that has a very odd sound to its exhaust. If I had to describe it, I would say it sounds like the Willie Wonka bubble-car from the old Gene Wilder movie or maybe the sound of a kid blowing bubbles in their milk. Blurp, blurp, blurp. I've heard some bad sounding Mustangs here these past few years, one up the street from me sounds like he's running a Mercury 125 boat motor instead of a V6 or V8, but this Shelby is the oddest sounding thing I have ever heard, Mustang or otherwise. Anyone know if this is a thing with the newer Mustang Shelbys or if this person had something done to really mess with the sound?

 

It's probably got a big cam in it to cause it to sound like that.

 

Whatever it is, it really sounds strange. It's not just a lope, it really sounds 'wet'. Another way to describe it might be if you've ever heard a boat motor idling in a garbage can while being worked on. It only sounds like this when idling and cleans up under acceleration, so I guess it could be the cam. It's just really, really wierd sounding. I don't know if I can get a decent recording of it, but I'll try.